Separation method and system for mixture of ethanol, diphenyl carbonate and diphenyl carbonate

Abstract

The invention relates to a separation method for a mixture of ethanol, diphenyl carbonate and diphenyl carbonate. The method comprises the following steps: feeding a thermal solution of ternary mixedorganic waste liquor of ethanol, DPC and DBP into a crystallizer to be cooled circularly, wherein the feed liquid temperature is reduced to be lower than constant temperature; then separating the feedliquid through a centrifugal machine, wherein solid crystals are DPC, and a liquid is a mixed solution of ethanol and DBP; feeding the mixed solution of ethanol and DBP into an evaporator, controlling the quantity of steam and the material feeding amount by adopting a temperature variable of the evaporator, and evaporating and separating the mixed solution, wherein ethanol escapes from the upperpart and is cooled by circulating cooling water, to obtain an ethanol liquid; a DBP solution flows from the lower part. A separation system for the mixture of ethanol, diphenyl carbonate and diphenylcarbonate is used for achieving the method. The method is simple to operate, finishes thorough separation at a relatively low temperature, the main contents of separated DPC and ethanol reach 98.5% orhigher, the main contents of DBP also reach 97.0% or higher, a recycling demand is met, material waste is avoided, the cost is reduced, and the environment is protected.

Description

technical field [0001] The invention relates to the separation of membrane-making waste liquid, in particular to a method for separating mixed organic matter of ethanol, diphenyl carbonate and dibutyl ester. Background technique [0002] In recent years, with the continuous improvement of our living standards, people pay more and more attention to environmental protection, especially the protection and recycling of water resources, which has led to the rapid development of the organic membrane industry. [0003] In the PVDF membrane industry, diphenyl carbonate (DPC) and dibutyl ester (DBP) are widely used as polymer intergranular fillers, and the formation of micropores in polymer membranes requires extraction and cleaning with absolute ethanol , Diphenyl carbonate (DPC) and dibutyl ester (DBP) are dissolved in ethanol solvent to generate a large amount of ternary organic waste liquid, which must be treated by scientific methods, otherwise, it will cause waste of raw materi...

AI Technical Summary

Problems solved by technology

[0003] In the PVDF membrane industry, diphenyl carbonate (DPC) and dibutyl ester (DBP) are widely used as polymer intergranular fillers, and the formation of micropores in polymer membranes requires extraction and cleaning with absolute ethanol , Diphenyl carbonate (DPC) and dibutyl ester (DBP) are dissolved in ethanol solvent to generate a large amount of ternary organic waste liquid, which must be treated by scientific methods, otherwise, it will cause waste of raw materials, Rising costs and endangering the environment we depend on

[0004] The separation of this kind of ternary organic waste liquid is relatively difficult. The commonly used method in the past is vacuum distillation, which uses the difference in boiling point of each component to separate. DPC is distilled off, and finally DBP remains

The whole production process is intermittent operation, which requires a high degree of vacuum and high temperature rise, so the energy consumption is high, and substances containing phenol will be produced during the rectification process, which is highly toxic and pollutes the environment

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